Portgas D. Ace is one of the most formidable characters in the One Piece universe, and his powers stem from his consumption of the Mera Mera no Mi — a Logia-type Devil Fruit that allows him to create, control, and transform into fire at will. His mastery over this ability made him a force to be reckoned with, both in combat and in presence.

Fire Manipulation (Mera Mera no Mi)

Ace’s primary power is his ability to become living fire. He can generate flames from any part of his body, shape them into attacks, and even ignite objects without physical contact. His techniques include "Hiken" (Fire Fist), a flaming punch that scorches enemies on impact, and "Inazuma" (Lightning), which extends fire from his fists in rapid succession. He could also launch fireballs, create fiery whirlwinds, and unleash massive blasts like the devastating "Prominence."

Combat and Physical Prowess

Before inheriting his Devil Fruit, Ace trained under the Whitebeard Pirates, one of the strongest crews in the world. His raw physical strength was already immense, and when combined with his fire abilities, he could deliver blows that burned as much as they shattered. Ace was also a skilled tactician and hand-to-hand combatant, capable of holding his own against Admirals and Yonko-level threats.

Limitations and Weaknesses

Like all Devil Fruit users, Ace was vulnerable to the sea’s nullifying effect, which stripped him of his powers if submerged. Additionally, while fire-based attacks could be resisted or countered by certain materials or abilities (like Logia immunity or Haki), Ace had to rely on precision and creativity to overcome these challenges. He also could not control fire outside his immediate vicinity, limiting the range of some techniques.

Notable Feats

Ace’s power was proven in several key moments: he fought admirably against the Admiral Akainu, survived multiple engagements with powerful Marines, and played a critical role in the Summit War of Marineford. His final act — launching a last Prominence toward Akainu before his death — remains one of the most iconic uses of his fire abilities.